1. Field of the Invention
The present invention relates to an electric shaver and more particularly to an improved cutter head section in an electric shaver.
2. Prior Art
Electric shavers are generally constructed from a main body case and a cutter head section. The main body case is held in hand during shaving, and it contains an electric motor, a power supply switch and a power supply that supplies power to the electric motor. The cutter head section is mounted on the upper portion of the main body case, and it contains an outer cutter and inner cutter.
In recent electric shavers, the cutter head sections are designed so as to pivot. In other words, the cutter head section pivots with respect to the main body case in accordance with the shape of the face (thus so-called xe2x80x9cswinging of the headxe2x80x9d) when the main body case is held in hand and the electric shaver is moved with the outer cutter pressed against the skin. As a result, the outer cutter can be held in tight contact with the skin for a longer period of time to cut hair more efficiently. Such electric shavers have been put on the market
Such a swinging-head structure is generally realized by attaching the cutter head section to the upper portion of the main body case so that the cutter head section can pivot through a specified angle about a single predetermined axial line. In one example, this axial line is set parallel to the direction of width of the main body case as disclosed in Japanese Patent Application Laid-Open (Kokai) No. H6-126043.
However, in the above head-swinging structure, the pivoting direction of the cutter head section with respect to the main body case is fixed. As a result, the outer cutter cannot always be caused to make a snug contact with the skin when the cutter head section is merely moved while the electric shaver is being moved along the surface of the face. This is because the face surface is uneven, and there are variations in shape. Accordingly, the user needs to incline the main body case, which is held in hand, in order to achieve an appropriate match with the contour of the skin. Thus, the conventional electric shavers are not quite convenient for actual use.
Accordingly, the object of the present invention is to solve the above-described problems.
More specifically, the object of the present invention is to provide an electric shaver in which a cutter head section can be moved in all directions with respect to the main body case of the electric shaver upon receipt of an external force from the skin
Furthermore, the object of the present invention is to provide an electric shaver in which the outer cutter is able to make a snug contact with the skin surfaces of the face hat has a varying contour during shaving.
The above-described objects are accomplished by a unique structure for an electric shaver that comprises: a main body case which contains an electric motor, and a cutter head section which contains an outer cutter and an inner cutter and is provided on an upper portion of the main body case, and the unique structure of the present invention is that
a supporting member which is comprised of a supporting plate body and leg portions is provided in an upper portion of the main body case via the leg portions that consist of elastic material disposed on both ends of the supporting plate body, and
the cutter head section is mounted on the thus provided supporting plate body of the supporting member.
In the above unique structure, the cutter head section is fastened to the supporting member, and this supporting member is installed in the upper portion of the main body case via elastic leg portions.
Accordingly, when, upon use of the shaver, the cutter head section contacts the skin and receives an external force from the skin, the leg portions undergo elastic deformation in accordance with the magnitude and direction of the external force. As a result, the cutter head section, more specifically the outer cutter that is inside the cutter head section and contacts directly with the skin, is moved all directions with respect to the main body case. In other words, the outer cutter makes a swivel motion without any specified fulcrum or specified axial line and makes a constant snug contact with the skin.
When the cutter head section is removed from the skin, the elastically deformed leg portions return to their original shape, and as a result the cutter head section also returns to its initial position with respect to the main body case.
In the above electric shaver, the supporting member is constructed from a plate spring in which both ends thereof are bent in the same direction to form the leg portions, and a plateform portion located between the leg portions is used as the supporting plate body. Thus, the structure of the supporting member is simple, and the number of components required is small. Also, the cost of the shaver can be reduced.
Furthermore, in the electric shaver of the present invention, the inner cutter is provided so as to perform a reciprocating motion with respect to the outer cutter. In this case, it is preferable to provide, inside the cutter head section, a conversion mechanism that converts the rotational motion of the output shaft of the electric motor into a linear motion that causes the inner cutter to perform the reciprocating motion.
With this structure, the leg portions made from elastic material is interposed between the conversion mechanism, which converts the rotational motion into a linear motion and generates the greatest vibration, and the main body case that is held in hand during the use of the shaver. Accordingly, the vibration generated by the conversion mechanism is absorbed by the leg portions, and the vibration transmitted to the main body case is reduced. Unpleasant vibrations to the user are thus avoided, and the convenience of use is improved.
Furthermore, a coil spring is mounted on an output shaft of the electric motor so that the rotational motion of the output shaft is transmitted to the interior of the cutter head section via the coil spring. With this structure, the rotational motion is reliably transmitted to the cutter head section or to the inner cutter while the coil spring deforms in accordance with the deformation of the leg portion of the supporting member. Moreover, the cost of parts is greatly reduced compared to the structure that uses an expandable universal joint. Also, since the structure is simple, malfunction of the shaver can be expected to be less.
Furthermore, in the above electric shaver of the present invention, locking assemblies are provided in the main body case. The locking assemblies are set at a deformation-restricting position in which the locking assemblies contact the undersurface of the supporting plate body and restrain an elastic deformation of the leg portions and at a deformation-permitting position in which the locking assemblies are separated from the undersurface of the supporting plate body and permit the elastic deformation of the leg portions. More specifically, each the locking assembly is provided with a supporting element, and one end of the supporting element is pivotally provided so that the other end is movable in a circular arc.
With this structure, it is possible to regulate the movement of the cutter head section with respect to the main body case. Hair can be thus shaved with the cutter head section pressed firmly against the skin while the user tilts and moves the main body case in accordance with the contour of the skin. It is, accordingly, possible for the user to shave with his desired angle.